Can't log in to main mail account

Can't log in to main mail account

I can't get logged into my main mail account (will private message support staff with account login) as it says that it has either an invalid username or password. I use a password manager that handles my passwords and have not touched my account settings. I've only had Zoho for a a few days now and it's been nothing but problems and when it comes to the support end of things, it's been taking, on average, 24 hours to get a single response. I've called, emailed and now I'm posting here because this will be the third day I'll be left without email and my clients aren't happy about that at all. 

I've called, emailed and am now posting here because I have time sensitive emails I need to retrieve and it's impossible at the moment.

Please help me get this resolved.